The present invention relates to a compliant wafer prober docking adapter for use in a docking system for accurately aligning an electronic test head to a wafer prober. Such docking systems are described, for example, in the above identified U.S. Pat. No. 5,552,701, the details of which are hereby incorporated by reference.
Prior art wafer probers and test heads are rigid devices, which can make it difficult to achieve a precise alignment between the test head and the wafer prober. For alignment purposes, the surface of the test head (tester) should be planar to the surface of the wafer prober (wafer). The test head and wafer prober both have large masses, which makes it extremely difficult to quickly align their respective planes to one another. It would be very desirable to mate the two surfaces accurately and quickly. The prior art approaches have difficulty in achieving this capability because of the rigidity and large masses involved. In addition, damage to one and/or another of the surfaces can occur when trying to have one massive planar surface mate with another.
In the prior art, in order to speed up the mating of the test system to the wafer prober, an adapter is rigidly affixed to the test head itself such that the test head is moved down upon the wafer. The probe tips are aligned to the wafer by moving the test head (a large mass) around while looking through a periscope through the middle of the test head. In such an awkward process, it frequently takes two persons working together for a long period of time to coordinate on properly aligning the two large masses, where one person views from the bottom of the locking mechanism which is to be engaged so as to hold the head in a locked position and the other person (usually on a ladder) views how the probes are aligned to the wafer.
In view of the foregoing, it would be very desirable to provide an improved wafer prober docking adapter for use in docking systems for accurately and quickly aligning an electronic test set to a wafer prober.